Check Yourself

Consistent training helps a runner lose weight, get in shape, and gear up for a race. But it's possible to have too much of a good thing, whether you're logging 80 miles a week or 18. "The problem isn't a matter of too much training but of too little rest," says John Raglin, Ph.D., who's studied overtraining for more than two decades. "It's a syndrome, with a constellation of symptoms that occur at different frequencies in different people."

Early signs of overtraining include loss of energy and frequent fatigue. A runner's legs also might feel heavy and tired, even after a day off. Anxiety and irritability are other indicators. And at the extreme—but not uncommon—end, a runner who blasts through all the warning signals may wind up sick or even depressed.

"When athletes start to see their performance slide, they often panic and train more," says Raglin. "They do exactly what they should not do." Before you go too far, learn how to recognize—and avoid—the most common overtraining pitfalls.

You want to amp up mileage too soon after an injury.THE FIX: Taking the fully prescribed time off to rehab has a similar effect to a taper period, says Bobby McGee, a former Olympic coach and author of Magical Running. Your body needs this time to repair and rest so it can return to its normal state. "An athlete approaching the end of rehab has to remind himself constantly, If I make a mistake now, I could be out for six months or more," Raglin says. Take advantage of the downtime to write out a long-range game plan. Having something down on paper, he says, "gives athletes a record to stay honest and remain objective, rather than putting a positive slant on lingering symptoms."

You decide to enter a race that's just a few short weeks away and are now trying to train in a condensed time frame.THE FIX: "An upcoming event galvanizes runners," McGee says. "Even if the period leading up to it is logically too short for their tried-and-true plan, they try to cram in the workouts that proved effective before." That's asking for trouble, McGee says. Go ahead and toe the line, but set your ego aside. Rather than trying to PR, for example, choose to run just for fun or to help pace a slower friend. Above all, "make a plan that is aspirational but plausible."

You've set a lofty goal but haven't adjusted your personal life to accommodate your additional training time.THE FIX: Even if you've found the right workout load to help you PR or qualify for Boston, other stresses—deadlines, poor sleep, family worries—can push you over the edge. It's okay to set the bar high, says Raglin, but pay close attention to your personal needs. Proper nutrition, solid sleep, and a good handle on life's daily pressures become critical for an athlete who is also striving for a particular running achievement. Be open to asking family members and friends to pitch in during your peak training, for example. While you can't slack off at work, you can ask your boss to help you prioritize your projects. And if you find yourself overly tired, you may need to scale back your mileage so you can get more shut-eye. Tracking energy level and emotions in your training log "can be a very useful reality check," says Kate Hays, Ph.D., a sports psychologist in Toronto. "Runners nearing a danger zone might be able to stop in time to make changes."You want to keep up with hard-core runner friends.THE FIX: Witnessing others' workouts and racing success can tempt you to emulate their routine, even if it's more than your body can tolerate. "Runners often think that motivation and extra effort will recalibrate their bodies, but they might not," says Raglin. Ask yourself how interaction with more serious athletes makes you feel, advises Hays. If you dwell on your differences, you're better off limiting workouts with the speed demon to once every couple of weeks (or months). And keep the running talk to a minimum whenever you're together. "Save the competition for race day," she says.

You were sick last week and want to squeeze in some extra miles to make up for it.THE FIX: Realize that even professional athletes rarely complete their set training schedule as it was written, says McGee. Accept the missed mileage by adopting this mind-set: Workouts are not missed or lost; what you did on that day was what your body required that day.

You're living in the past.THE FIX: It's common for runners, as they get older, to want to maintain the pace they used to be able to hit—whether they PR'ed last summer or last decade. "People age so differently, but the reality can smack you in the face," Raglin says. Instead of chasing past dreams, he advises reassessing goals and finding new—equally important—reasons to run that have nothing to do with the time on the clock or miles tallied at the end of each week. If the desire to hit a certain pace is still strong, he suggests focusing on a shorter distance and judging your workouts more on quality versus quantity.

FEEL better: Get to know your resting heart rate by taking your pulse first thing; an increase of five beats per minute or more can indicate overtraining.

On the BrinkThink you have a handle on overtraining syndrome? We set the record straight on some popular misconceptions

FICTION: Newbies are more likely to overtrain than experienced runners.FACT: World-class athletes are twice as likely to overtrain as nonelites.

FICTION: A blood test is the best way to diagnose overtraining syndrome.FACT: Emotional or behavioral factors are more accurate measures of overtraining than any physical test doctors perform.

FICTION: If a runner still feels fatigued following a day of rest, he's probably experiencing overtraining.FACT: It takes three to five days to know. If he still feels sluggish, and shows no other signs of illness, then there's a good chance he's overtraining.

FICTION: The effects of overtraining are seen only in adult athletes.FACT: Middle-school-age athletes, as young as 12, have shown signs of overtraining syndrome.

FICTION: Overtraining syndrome can occur when a runner logs more than 40 miles each week.FACT: Mileage has nothing to do with overtraining syndrome: Any time a runner doesn't allow for proper recovery, he's at risk of facing adverse effects.

WHEN EXPOSED TO REGULAR, FAIRLY INTENSE RUNNING ROUTINES, ONE OUT OF THREE PEOPLE WILL OVERTRAIN AT SOME POINT.